The Legal Limit Of THC In Hemp And The Fight To Change It

In this post –

A plant by many names

Cannabis has been known by many names throughout history, which makes sense considering that it develops completely differently in warmer climates than it does in colder ones. As a result, some cannabis varieties have more or less flowering, longer or shorter stalks, and yes–more or less THC. But despite the differences in appearance, use, and even genetics, scientists confirm that cannabis consists of only species–Cannabis Sativa. 

It wasn’t until the 1970’s, after cannabis was legally banned, that researchers made an effort to separate the various subtypes into nominally separate species. This was the birth of “hemp” as wedefine it today.

An arbitrary definition for hemp vs. cannabis

In 1973, Canadian researcher Ernest Small and his partner Arthur Cronquist needed a benchmark to separate hemp from Cannabis for their taxonomy study. They chose THC content as the marker and arbitrarily decided .03% would be the cutoff between the two. 

Years later, Small stated in an interview that he and Cronquist never intended .3 to be a method of legal standardization. He indicated it was only meant to separate the subtypes for research purposes. But the intention didn’t matter. 

When it was time to legally define the difference between industrial hemp and “cannabis,” the illicit plant listed in the Controlled Substance Act of 1970, U.S. lawmakers opted to use Small’s .3% THC benchmark. 

Richard Rose, a veteran of the hemp foods industry for 25 years, discussed the topic of defining hemp in an article for Hemp Grower magazine, In it he says, “Thailand…mandates that cannabis containing 0-3-percent THC is classified as hemp; 3-9-percent THC is classified as adult-use, and any marijuana products greater than 9-percent THC are classified as medical and therefore more tightly regulated.” Rose also notes the UN defines hemp as “CBD:THC ratio >1.”

On the other end of the spectrum, EU regulators opted for a stricter limit of .2% THC. 


Why limit THC to 0.3% for hemp in the U.S.?

The vast differences in definitions means the .3% rule has no foundation in science, nor is it based on a globally recognized standard. But it’s where the U.S Farm Bill and the United States Department of Agriculture (USDA) stands today. 

Presumably, congress established these rules to prevent farmers from planting hemp and accidentally (or purposely) harvesting psychoactive cannabis instead. But farmers are suffering as a result. Due to the variability of the plant and its sensitivity to increased heat and humidity, growers struggle to find strains that maintain the expected threshold. 

The issue with limiting hemp to 0.3% THC

The issue is THC content often rises above .3% during flowering. Then naturally decreases as the plant continues to grow. But it doesn’t always decline below the limit and it can be difficult to determine whether the harvested crop is compliant until it’s too late. 

The difference between passing as legal hemp and testing above the limit sometimes rests on the exact time of harvest. Moreover, even after harvest, the cannabinoid content can change if the plant is exposed to excessive heat during storage. 

Hemp contains a compound known as THCA, which is the acidic precursor to THC. When exposed to warm conditions, THCA converts to THC, which can transform a formerly compliant crop into an illegal one overnight. And the proposed penalty for such transgressions is severe. 

Under the USDA’s Interim Final Rules for hemp cultivation, if a sample tests above 0.3% THC–adjusted for a “Measurement of Uncertainty”–the producer cannot sell the crop and it must be destroyed at his or her own expense. Moreover, current Crop Insurance does not cover farmers for this occurrence. 

The hemp industry’s fight to raise the limit

So how do we fix this problem? Some say genetic testing would help. But such procedures are expensive. They’re also inadequate due to the fact that many “hemp” plants are actually Cannabis sativa varieties bred to have low-THC and high CBD content. 

Fortunately, the USDA issued a temporary delay in February regarding enforcement of this rule. That means hemp producers are not required to dispose of hot hemp through the DEA or another law enforcement body until the department finalizes its rules in October.

Until then, farmers, lawmakers and activists are fighting to raise the .3% threshold to a more feasible limit. They propose a .5% to a 1% cap, which is in line with countries like Switzerland, and Western Australia. They say this would reduce the risk of dramatic financial loss to farmers and ensure healthy growth of the market.

In response, the USDA has not budged on its stance, citing legal limitations from the 2018 Farm Bill. In fact, the USDA’s own Agricultural Marketing Service Bruce Summers indicated any changes to these rules would require legislative action. That means congress must amend the Farm Bill before the USDA will change its rules. 

As the fight continues, opponents of the .3% limit are lobbying the U.S. government for change.  

ACS is tracking the THC-limit debate in real time. Check back often and jump to the section below for updates as the story develops.


Updates on the fight

Vote Hemp Petition:

In the U.S., Vote Hemp President, Eric Steenstra, is fighting to raise the .3% THC threshold. Mr. Steenstra says a limit of 1% would result in very few crops being destroyed and provide valuable time while the industry works on developing more stable varieties. His group is circulating a petition to do just that. Vote Hemp is seeking as many signatures as possible in the next month to support the fight. You can find the petition here.

ACS Laboratory’s testing panel and protocol is compliant with Florida’s Hemp Program. ACS meets federal requirements by testing to the standards of Florida, the strictest state. The compliance panel consists of:  Cannabinoid Potency,  Pesticides, Residual Solvents  (unless its flower), heavy metals, mycotoxins, moisture, microbiology. Contact ACS today.


Sign up to receive the latest news and information directly to your email inbox!


Sign up to receive the latest news and information directly to your email inbox.